the buttstock on my sx3 started getting loose all of the sudden this season. Happened twice. the first time i didnt think much about it and just pulled the buttpad off and tightened it back up but it did it again the last day of the season. Has anyone elses done this? If so did you contact winchester about it? just wondering if there is anything i should do outside of just torqueing it down as tight as I can and hope it doesnt loosen up again. Thanks

I agree with both statements....maybe, even LOW strength locker.I don't know what torque Winchester recommends on that stock nut, but I do know that my Ruger Shotgun manuals specify 4 lbs/ft. That ain't much.

My newest MP-153 had that issue as it turned out the stock where the nut/bolt attaches had a split in it ( I fell on the poor thing...lol), as a result it would not stay tight. I had to replace the stock. Not saying thats what it is in your case but might be worth checking.